Apple Watch Series 3 with Watch OS 6 Mail/Calendar sync issues

I use a modular watch face that correctly displays upcoming calendar events as a complication. Calendar events with notifications are coming through just fine. Same if I add an event via Siri.

But - if I go into either the calendar or the mail by itself, it say no events/no mail.

I’ve got it set to mirror my phone, which is working properly.

Any thoughts?

Give this a try: https://www.idownloadblog.com/2017/12/19/how-to-fix-contacts-calendar-sync-problems-apple-watch/

The Reset Sync Data option worked, I applied via phone, rebooted the watch and everything was back to normal. Thank you very much!